The present disclosure relates generally to the problem of achieving fast drying of a thermal inkjet ink on various substrates. There is currently a need for inkjet ink that dries quickly on non-porous and semi-porous materials.
Most of the thermal inkjet inks developed to date are designed to offer superior print quality on porous materials, such as paper (swellable and porous media) and cardboard, among others. These inks are fluids based predominantly in water, in combination with other specialty components, which include surfactants, biocides, humectants, and either a pigment or dye colorant or mixtures of both.
The drying mechanism of most water-based inkjet inks can be regarded as penetration driven, especially when applied to porous media. In contrast, the drying mechanism of inkjet inks on non-porous media is predominantly by evaporation of the ink components.
The use of aqueous-based inks for printing on porous, non-porous and semi-porous materials has been evaluated for industrial applications. Such industrial applications require the use of high speed printing and fast drying of the ink to meet the demands stemming from the high throughput required by the industrial situation. These can efficiently remove water from the printed media and consequently decrease the drying time of the ink. However, the heat radiators are expensive due to high energy costs. Furthermore, the heat has a negative impact on the properties of the media.
It has been found that media properties are altered when exposed to high heat conditions. For example, the media can lose its gloss, the paper can turn yellow, and the media can become deformed.
Fast drying ink compositions based on volatile ingredients have been reported using non-thermal inkjet technology. These include such inkjet technologies as piezoelectric inkjet (PIJ) and continuous inkjet (CIJ). Common ingredients found in these ink compositions include ketones (acetone, methylethylketone), esters (ethyl-, butyl-acetate), lower aliphatic chain alcohol (methanol), cyclic ethers (THF) and other highly volatile components used as the main solvent. However, the vast majority of these components has been regulated and has their use limited due to environmental considerations. Such environmental considerations relate to volatile organic compounds (VOC) emissions and other environmental awareness initiatives. Furthermore, those skilled in the art recognize that the use of these types of ingredients in combination with thermal inkjet ink may have poor performance issues associated with poor drive bubble formation, decap-affected performance, materials compatibility problems, etc. Thus, inkjet inks compatible with thermal inkjet which are based on fast evaporating components have been unknown.